The field of the present invention is devices for creating and applying mists, vapors, or sprays from a liquid, in medical, industrial, and household applications.
The eye is perhaps the most sensitive organ of the body. By contrast to other organs, the slightest touch of the cornea may be irritating and painful. Similarly, the membrane which covers the remainder of the eye, the conjunctiva, is so thin and delicate that it is normally invisible unless it becomes irritated. Both the cornea and conjunctiva are normally kept moist by the constant washing action of tears and blinking.
Because of its sensitivity, many common conditions may irritate the eye. Dry or polluted air, wind, bright light, swimming, dust or chemical fumes all produce eye irritation. Similarly, contact lenses are frequently irritating, especially if worn continuously throughout the day.
Surprisingly, few easy to use and effective methods to relax and comfort irritated eyes have been developed. To rid the eye of foreign objects, for example, a saline-filled "eye cup" or eye wash bottle is used. Since both are messy and inconvenient, it is not practical to use either for routine eye comfort. Another method of relieving seriously dry eyes caused by certain eye diseases employs a small specifically formulated prescription rod-shaped solid strip (Lacrisert.TM.) which is inserted under the lower eyelid. Over several hours, the strip dissolves into the tears and produces a soothing liquid film. Since this product is available only by prescription, it is used only in limited and serious eye conditions.
For the vast majority of people, the only method of applying liquid to the eye is perhaps the first method ever invented--the eye drop. Many if not most substances intended for application to the eye, both over the counter (OTC) and prescription, are packaged in a container which has a built in "eye dropper". Unfortunately, dropping drops into the eye is awkward, inconvenient, uncomfortable and potentially dangerous. For any parent who has tried to apply drops of liquid into the eye of a small child, the prospect of repeating this frequently traumatic action is not appealing. Similarly, applying drops into one's own eye, especially if one's manual dexterity is not optimum, can be difficult and unpleasant and potentially dangerous to the eye. For many older people who need to frequently apply eye moistening liquids or eye medications because of chronic eye disease, eye drops can be very difficult to manage because of arthritis, injury or poor hand-eye coordination.
In order to effectively administer a drop to any eye using an eye dropper, the user must position the pointed dropper tip close to the delicate and sensitive cornea. A slightly unsteady hand or sudden movement may cause the tip to hit the eye and cause pain, damage and potentially vision-threatening damage. The awareness of this possibility may be keenly appreciated by observing an average user attempt to self-administer eye drops. For this reason, it is dangerous to use eye drops when the user is in motion or may be bumped in a crowded area. The use of a dropper bottle on an airplane, for example, may subject the user to significant risk given the possibility of an unexpected jolt from air turbulence or a bump from a fellow passenger.
In ocular drug therapy, it is important that the patient deliver the correct amount of drug to the eye. Because of the difficulty of using and properly aiming eye drops, however, some medication usually drips down the face, thus missing its intended therapeutic target. In case of vision-saving anti-glaucoma drugs or antibiotics, under or over-administration of the drug may have serious repercussions.
Due to the potentially vision-threatening nature of many ocular conditions which require prescription medications, strict patient compliance with the physician's recommended dosing schedule is very important. Unfortunately, ocular drugs administered by eye drops are unpleasant and difficult to use for many people which results in relatively poor compliance with the physician's instructions and potentially serious consequences.
For many eye conditions and diseases, incidence increases with advancing age. As age increases, however, the manual dexterity and eye-hand coordination required for self-administration of eye drops may be greatly reduced. It is difficult enough for a young, healthy person to tilt the head back, hold an eye lid open with one hand while trying to aim and drop liquid into the eye with the other hand. For many older people, it is essentially impossible. The fact that many ocular drugs must be administered as often as four times per day further compounds the potential problem. This unfortunate set of common circumstances sets into motion a potentially vicious cycle which frequently leads to inadequate use of vision-saving eye medications with potentially catastrophic results. Accordingly, an improved way of delivering eye medication would be of great benefit.
The eye is also very susceptible to accidental injury. The inadvertent introduction of chemicals or foreign bodies into the eye constitutes a potential medical emergency. Rapid intervention by flushing the eye with an inert liquid can potentially prevent irreversible loss of vision. Unfortunately, access to eye wash bottles or fountains in schools, laboratories, industrial settings, at home or during recreational activities is sometimes limited. A portable and easy to use eye wash device would be very useful to help reduce eye injury from foreign chemicals or objects.
Accordingly, there remains a need for a device for safely, accurately and conveniently administering drugs or other substances to the eye.
Consumers are increasingly recognizing that cosmetics and personal skin care products have the ability to provide more than just a superficial change in skin appearance. Cosmetics may also provide protection against the potentially damaging ultraviolet rays of the sun and can protect against the irritating and potentially skin-threatening environmental conditions which lead to irritation and premature signs of aging. For this reason, consumers recognize that to obtain optimum benefit, skin-protective cosmetics must be applied more often then only during the morning and evening rituals common to many customers.
It is, however, awkward and inconvenient for many people to carry multiple jars and bottles during the day and equally troublesome to open containers which may spill and apply cosmetics or fragrances in many social or business environments.
Many women and men would like to use skin care products throughout the day but do not because of the inconvenience of conventional application methods. Most skin care products require the customer to use their fingers or hands to apply and evenly spread the product on the skin. Touching the skin with the fingers, especially for acne-prone people, increases the chances of skin irritation and blemishes. Rubbing products into the skin can also leave greasy or oil residues which may remain on the hands and can be transferred to papers, equipment or other people and forces customers to go to the restroom to wash their hands. This inconvenience results in many people limiting their use of skin care products to the home.
Similarly, the approximately one in ten Americans who wear contact lenses are acutely aware of chemical residues on their hands which may contaminate the lenses when they are removed and cleaned during the day. This concern is especially applicable to skin "treatment" products in general and sun screen products in particular since many adhere to the skin for extended periods of time even after exposure to water. For this reason, many contact lens wearers do not use sun screen or skin care products during the day unless they have ready access to soap and water.
Another group of people may find it cumbersome or unwieldy to apply skin care products due to their particular environment. Skiers, for example, frequently need facial moisturizers and sunscreens due to the dry, windy and ultraviolet-rich environment of the mountains, but find it awkward to carry and use multiple bottles or tubes of products. Airline travelers have a similar need for frequent facial moisturization due to the low ambient humidity of airplane cabins, but many find it inconvenient to carry products which may leak or spill in the crowded, depressurized cabin environment.
Many men and women are exposed to low humidity environments which increase transepidermal water loss and produce dry, chapped and irritated skin. Air conditioning, forced air heating, airplane travel, high altitudes, desert climates and many other factors result in the frequent need for facial moisturizers. In many of these environments, however, it is not convenient to carry or use moisturizing products.
During the last several years, consumers have also become acutely aware of the role of ultraviolet radiation in producing sun burn and long-term skin photoaging. Both men and women gravitate towards sun protection products with "light", non-greasy formulations which are invisible during wear.
A shortcoming of known aerosol and pump sprays for delivering skin care, fragrances and cosmetic products is the inability to accurately control the amount of spray or mist produced. In addition, the pattern and shape of the spray can be unpredictable, irregular, and vary with the pressure of the propellant or pumping action. Spray velocity and droplet size can also be inconsistent and difficult to control.
In a conventional pump, the spray can be difficult to aim and the spray pattern is poorly focused. Furthermore, pump sprays deliver only a fixed amount of liquid which may exceed the amount desired by a consumer. This lack of control of pump sprays frequently results in products staining clothes, getting into the hair or being sprayed in the eyes or in areas of skin not desired.
Many "high-end", expensive cosmetic formulations use ingredients which are believed to provide skin-rejuvenating or protection properties. These ingredients include lipids (e.g. ceramide derivatives); glycosaminoglycans (mucopolysaccharides, e.g. hyaluronic acid); "exotic proteins" (e.g. fibronectin, placental proteins); nucleic acids, vitamins (e.g. vitamins C and E), among others.
In many instances, these ingredients are formulated in encapsulated, unit dose vials or capsules to protect the products from exposure to air or the environment which may oxidize or otherwise chemically degrade the ingredients. However, these products can be difficult to apply without waste and are relatively expensive.
Many chemicals used in cosmetics can oxidize due to contact with oxygen in the air. Instability of cosmetic ingredients can limit the circumstances in which desired ingredients can be used or may prevent their use entirely. For example, ascorbic acid which has been reported to have beneficial skin-protective effects in humans is unstable when in solution and exposed to air. Many other ingredients derived from "natural" sources such as peptides, vitamins and skin lipids have similar instability when formulated in conventional products. There is accordingly a need for an improved way of applying cosmetics and other skin care products.
Preservatives in cosmetics and skin care products produce skin irritation in many sensitive skin consumers. Nevertheless, conventional application methods, especially those requiring the user to touch the product with the fingers, require the use of preservatives since microbial contamination is difficult to prevent. Accordingly, there is a need for a device which can hold and dispense preservative-free skin care products while keeping products free of microbial contamination.
Lubricants, paints, solvents, etc. are frequently applied to many products found in the home. Frequent sites of lubricant application include: door hinges, door locks, nuts and bolts and screws, fans, motors, drawers, windows and many mechanical devices. A common feature of all of these uses is the small size of the lubricated area and its frequent location adjacent to rugs, curtains, walls or other objects which would be stained or otherwise harmed by the inadvertent contact with lubricants.
Conventional aerosol sprays used to dispense many lubricants are notorious for their tendency to splash, ricochet and drip during application. Moreover, these aerosol sprays can be difficult to aim and control. Some aerosol sprays also use propellants which are damaging to the environment. Thus, there remains a need for a device for spraying lubricants, paints and other liquids which avoids these disadvantages of conventional aerosol sprayers.